1. Field of the Invention
The invention herein relates to a system of protecting an electrical cord from damage, and more particularly to a system of protecting the electrical cord of an electrical power tool from damage which can be encountered by the function of the tool itself, such as being cut by the blade of a power saw.
2. Overview of Prior Art
It is a common occurrence that accidents happen in the area of damaging the cords of power tools, especially power saws. The necessity of the cord in close proximity to the workings of the tool predispose the combination to damage and danger. It is unfortunate that little has been done in an attempt to correct this problem.
Shurtz in U.S. Pat. No. 3,611,265 discloses a spring holder with an enlarged loop on one end thereof. The spring holder surrounds the cord and places the cord in tension from the tool housing to the plug. This tensioning force causes the cord to be directed away from the tool. The obvious limitations include if the length of the cord on the tool is to great the function of the coil in this manner is virtually useless. Secondly, the spring end that is in contact with the tool housing will attempt to fit flat up against that surface and extend the cord perpendicular to that surface, keeping in mind that the weight of the cord will cause it to fall as it extends away from the tool. If the surface is at an angle that positions the cord in a downward direction the combination of this and the cord weight will put the cord directly on the workpiece, even if the cord is of the proper length to make the device potentially functional. The result is a very limited potential for the product to be effective.
In U.S. Pat. No. 4,149,765 to Mortelmans, a system of storage of a coiled electrical cord on an appliance is disclosed. In this the primary purpose is in the interest of space saving and convenience of the user in that the cord is automatically stored inside the housing of the appliance such as a vacuum cleaner. If the device was incorporated on a power tool the results would be of minimal consequence in that the cord still freely extends out of the appliance.
Similarly, Witt discloses in U.S. Pat. No. 3,068,316 a cord shortening holder which is comprised of a self contained unit that coils surplus lengths of electrical cord. The unit is not obvious in its connection to a power tool housing and if it was how it would prevent the cord from coming into contact with the functional element of the power tool. Therefore the problems disclosed herein are not adequately addressed by this device.
More common are locking devices that are intended to prevent inadvertent disconnection of the cord from an electrical appliance or tool. Bunyea et al., in U.S. Pat. No. 4,875,879 discloses a cord retainer for a power tool such as a trimmer or drill. This includes a cam that contacts the cord which is captured on the opposite side, thus securing the cord's position in relation to the handle of the tool. The cord still extends directly out of the tool's handle thus doing little to prevent accidental contact of the cord and the cutting edge of the tool.
LaCoursiere, Sr. et al. discloses a cage tier enclosing electrical cords in U.S. Pat. No. 3,871,731. This is limited to securing a plug into a wall socket or tow adjacent mating ends of a pair of cords. This provides no system of keeping the cord from the work area of a tool.
The following three U.S. Pat. Nos.: 4,206,961; 3,922,055 and 3,097,034 disclosed by Cifalde, McGregor and Jamrosy respectively all disclose methods of preventing unwanted disconnection of mating plug ends of adjacent electrical cords. In each case the application would not be anticipated in an application to somehow prevent the cord from coming in contact with the workings of a tool. The devices are all restricted to a spring or coil that applies a frictional force to the cords thereby preventing them from pulling away from each other when they are plugged in one to another. None of the disclosed art adequately addresses the problem of preventing contact of the cord with the working area of power tools.